The present invention relates to a new and improved construction of wall covering material containing at its rear face an elastic, gas pervious foam plastic layer containing flame-retarding additives and confronting, during use of the wall covering material, the wall which is to be covered, and further embodies a cover layer at its front face which, during use, faces the viewer of the wall covering material and contains fibers. The entire heat composite possesses heat insulating, sound absorbing and flame-retarding properties. In particular, the wall covering material is essentially a predominantly flat structure which can be applied to a wall in the manner of wallpaper.
Insulation materials which are suitable as wall coverings, for instance styrene foams, indeed possess a limited decorative effect, for instance by structuring the same, but no flame-retarding properties. Generally, they require further finishing, for instance by coating or tapestrying. As a rule, however, such does not tend to eliminate the pressure sensitivity of the aforementioned insulating materials, and therefore apart from the previously discussed operations which are complicated and time-consuming, it is necessary to resort to other protective measures.
Other insulating materials, which do have flame-retarding properties, such as rockwool, do not however have any decorative effect.
Decorative materials, for instance carpets, which also have a certain degree of insulation capability, are not adequately flame inhibiting, and furthermore, they are expensive so that they only can be used in exceptional instances.
In Swiss Pat. No. 587,119 there is disclosed a wall covering material which possesses at its rear face, confronting the wall to be covered during use, a foam plastic layer containing flame-retarding additives and at its front face, which confronts the observer during use, a decorative cover layer containing textile fibers. The entire wall covering material or composite possesses heat insulating, sound absorbing, flame-retarding and decorative properties. The foam plastic layer should have an extensive, cellular or expanded rubber-like restoring capability in order to reduce the pressure or compression sensitivity. To render possible breathing of the wall, the entire wall covering material should be gas pervious.
However, such wall covering material is afflicted with the drawback that, owing to its elastic foam plastic layer, there can be formed unsteady joints and drawn-in joints, if the elastic foam plastic layer is relatively soft. Therefore, it is desirable if the foam plastic layer possesses a certain rigidity, which only however can be obtained by increasing the content of filler material, if the material still should have pressure or compression sensitivity. This increase in the filler material or filler is however associated with the disadvantage that there is reduced the quantity of air which is encapsulated in the aerated or foam plastics, which, in turn, appreciably reduces the insulating properties.